Patents by Inventor Douglas S. Pfahl

Douglas S. Pfahl has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Dual isolated mode controller for injection molding machine
    Patent number: 6682332
    Abstract: An injection molding apparatus includes a control system for controlling the injection of fluid molding material during an injection cycle. The control system includes a controller for generating control signals and a servo control circuit responsive to the control signals for controlling the injection of the fluid molding material. The servo control circuit implements a first control mode which controls only a velocity of the fluid molding material during a first part of the injection cycle and a second control mode which controls only a pressure of the fluid molding material during a second part of the injection cycle.
    Type: Grant
    Filed: August 14, 2001
    Date of Patent: January 27, 2004
    Assignee: Alcoa Inc.
    Inventor: Douglas S. Pfahl
  • Dual isolated mode controller for injection molding machine
    Publication number: 20030035854
    Abstract: An injection molding apparatus includes a control system for controlling the injection of fluid molding material during an injection cycle. The control system includes a controller for generating control signals and a servo control circuit responsive to the control signals for controlling the injection of the fluid molding material. The servo control circuit implements a first control mode which controls only a velocity of the fluid molding material during a first part of the injection cycle and a second control mode which controls only a pressure of the fluid molding material during a second part of the injection cycle.
    Type: Application
    Filed: August 14, 2001
    Publication date: February 20, 2003
    Applicant: Alcoa Inc.
    Inventor: Douglas S. Pfahl